1. Field of the Invention
The present invention relates to an improvement in processing of embossed translucent flexible sheet material, and more particularly to the coating of embossed lenslets with inking solutions on at least one surface of the sheet material to thereby generate visual display patterns.
2. Prior Art
In the past, the coloring or inking of lenslets embossed on a synthetic plastic material capable of producing a wide variety of optical effects has been relatively simple as a result of the fact that the sheet material is rigid and the individual lenslets are relatively large in size. For example, such prior art sheet material is approximately 0.015 inches thick with lenslets having a diameter of approximately 0.010 inches embossed thereon.
The technique for coloring the large lenslets, as will be explained in greater detail hereinbelow, is relatively straightforward and employs the use of conventional printing rollers. A first roller is suspended in a bath of ink for transferring the ink to a second roller which then transfers the ink to the lenslets on the sheet material. This process is satisfactory for coloring such large lenslets of rigid material. However, if one were to use a flexible material such as a thin sheet of flexible material (e.g., thickness of about 0.0075 inches) having a multiplicity of very fine lenslets located thereon, the prior art printing process is not adequate. That is, the prior art printing technique not only covers each of the very fine lenslets (e.g., diameter of 0.004 to 0.005 inches) but also floods the very fine valleys therebetween, which obfuscates any possible visual patterns that may be produced.